Mechanism for closing sliding doors.



I W. KBATING. MECHANISM FOR GLQSING SLIDING DOORS.

APPLICATION FILED APR.10,1008.

Patented May 4, 19090 Egflf lllll'llll INVENTOR I TII "OI-II 'IYIII m, Illlllml, D A

WILLIAM KEATING, OF NEW YORK, N. Y.

MECHANISM FOR CLOSING SLIDING DOORS.

Specification of Letters Patent.

Patented May 4, 1909.

Application filed April 10, 1908. Serial No. 426,218.

To all 107mm it may COHCCWL.

Be it humor that I, \E'iLLiAM HEATING, a citizen of the United States, andv a resident of the city of New York, in the county of New York and State of New York, Uniter'l States of America, have invented certain n and useful improvements in iri echanism for (losing e liding Doors, of hich the folio ing a specification.

My invention relates to mechanism for closing sliding doors and especially to certain applian es hich maybe used in conjunction nith such doors to improve upon their cfiiciency and ease of o eration.

To these ends my invention resides in the construction and arrangement of parts described in the following specification, the novel features whereof are set forth in the appended claims.

Referring to the drawings, Figure 1 is a front elevation of a double sliding door of ordinary construction with my invention applied thereto. Fig. 2 is a sectional end elevation on an enlarged. scale of some of the parts shown in Fig. l, the section in this figure being taken on the line 22 of Fig. 1. in this figure one of the parts is broken away to more clearly slurs the wnstruction. Fig. 3 is a s rtional elevation on a still larger scale, shoning a detail of construction of a SCl'GY-f and gear mechanism nhich I u e in carrying out my invent-ion.

Like characters of reference designate corresponding parts in all of the figures.

10 and 1] designate the tv. 0 parts or sections of a double sliding door of ordinary construction which are supported. upon rail 12 by means of roller hangers A flexible cable 14, which passes over sheaves 15 and 16, is attached to the door section 10 at 1'7, and to the door section 11 at 18. This causes the movement of one of the door sections in either direction to be imparted to the other door section in the opposite direction. This arrangement forms no part of the present invention but is well-known in the art.

Aflixed to one of the door sections is a horizontally disposed toothed-rack 20. An internally threaded spur-gear 21 is in mesh with this rack at a position at one side of the door opening. The upper and lower surfaces of this gear member are provided with annular ball grooves 22 and 23. Similarly grooved collars 24 and 25 are placed directly above and below these surfaces and are supported from the side 19 of the structure which forms the door opening by means of brackets 26 va'l'iich are secured to a holding block 1Q upon the slde of the structure 19. A plurality of balls 27, 27 are interposed bey tar. eon these surfaces and collars and retained within the annular grooves. Thus the gear l member is held in a given position by halli hearings which permit it to rotate freely. 28 designates a spirally threaded vertical shaft which passes through the gear member l into e. hich tne threaded portion of the latter l fits formin a rotatable member on the shaft. l 1 b l This shaft has a tendency to move downvzard on account of its on 11 weight "which may y beaugmented by a'lhxmg a weight 29 at one i of 1ts ends.

30 is a bracket projecting from the holding block 19 for the purpose of guiding the shaft 28. This shaft 28 arranged to pass freely through the bracket 30, and. in order to decrease friction at this point, another ballhearing may be provided if desired.

31 is a rod or pin proj cting laterally from the threaded shaft 28 and provided with an antifriction roller 32. This roller is arranged to fit loosely Within a vertical slot 33 in a plate 34 which is supported by rods 35, aflixed to the holding block 19 The parts above described form a door closing device which operates as folloas: VJhenever the door section 10 is moved to the right to open the door the rack 20, engaging with the gear member 21, will cause the latter to rotate in one direction. This rotation of the gear member, acting upon the spirally threaded. shaft 28, will push the latter upward. because the pin 31 and the plate 34 prevent the latter from turning. Thus the v. eight 29 will be raised by the opening of the door. Obviously the door section 11 will at the same time be moved to the left. vrhenever the door is released, the operation will be reversed. The Weight 29 will now act upon and rotate the gear member 21 which, in turn, acting upon rack 20, will push the door section 10 to the left, and the latter, through its connecting mechanism, .will cause the door section 11 to move to the right until its movement is stopped by the two door sections coming together.

This device has many advantages among which are its ease of a lication to existing structures and its relia ility of action on account of the absence of springs. Doors of this type are commonly used in elevator shafts. Many of the accidents With eleva- 'hatchway doors.

tors are due to the faulty operation of the A positively acting door closing device in conjunction with such in stallations will consequently increase the safety of their operation. .Spring actuated devices becomes easily deranged. WVeights have been used for this purpose, but when hung by flexible straps or cables the latter are liable to break; and moreover, the installation of such an arrangement entails serious difficulties such as cutting open a part of the door frame. My device is selfcontained and may be readily applied to any sliding door, whether the same is a finished structure or only in process of erection.

I have designed the herein-described arrangements especially for use in conjunction with elevator doors, although, of course, I do not mean to limit myself to this use. it may be seen that elevator doors provided with this invention will be automatically closed.

hat I claim is:

1. An edgewise movable door, a frame therefor, a spirally threaded vertically in vable shaft mounted on said frame, a gear member on said shaft arranged to be rotated in one direction by a downward movement of the shaft, and connections between the gear member and the door for causing said rotation of the gear member to close the door.

2. An edgewise movable door, a frame therefor, a spirally threaded vertically movable shaft mounted on said frame, a weight affixed to said shaft, an internally threaded gear member on the shaft arranged to be rotated in one direction by a downward movement of the shaft, and connections between the gear member and the door for causing said rotation of the gear member to close the door.

A sliding door, a vertically movable weighted member at one side thereof, a rack on the door, and a gear connecting the vertically movable member with the rack whereby the downward movement of said shaft rotates the gear to close the door.

4. A sliding door, a spirally threaded vertically movable shaft, means for moving said shaft, an internally threaded member on the shaft, said. member being provided with gearteeth, and a rack on the door in mesh with said gear-teeth.

5. A sliding door, a door frame, a spirally threaded vertically movable shaft mounted on said frame, a weight affixed to said shaft, an internally threaded. member on the shaft, neans for preventing rotation of the shaft, the outer surface of said member being provided with gear-teeth, and a horizontally disposed rack on the door in mesh with said gear-teeth.

6. In combination with a sliding door, a door frame, a spirally threaded vertically movable shaft, a weight affixed to the shaft, a guiding bracket for the shaft, a plate for preventing rotation of the shaft, an internally threaded rotatable member on the shaft, the outer surface of said member being provided with gear-teeth, ball bearings for the rotatable member, a bracket for supporting said bearings, all of said parts being affixed to a common holding block upon the door-frame; and a horizontally disposed rack on the door in mesh with the gear-teeth on said member.

In testimon whereof I have signed my name to this specification in the presence of two subscribing witnesses.

\VILLIAh l KEATING.

\Vitnesses FRANK B. KLoPF, NORMAN O. HARRIS. 

